Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-02-06T16:24:08Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese arq unico - format ultimo -.pdf: 2516916 bytes, checksum: c42c076db5fb7574208f22ea8d7ced58 (MD5) / Made available in DSpace on 2017-02-06T16:24:08Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese arq unico - format ultimo -.pdf: 2516916 bytes, checksum: c42c076db5fb7574208f22ea8d7ced58 (MD5) Previous issue date: 2011-08-31 / O objetivo desse estudo foi comparar o impacto da suplementação materna no pós-parto imediato, com 400.000 UI vs 200.000UI de vitamina A nas concentrações séricas de retinol da criança, e estimar o período do efeito protetor na manutenção das concentrações séricas de retinol nas crianças, identificar a prevalência de hipovitaminose A e anemia aos seis meses e verificar a associação entre as concentrações de retinol e hemoglobina na criança. Ensaio clínico, randomizado, controlado e triplo cego, de base hospitalar em duas maternidades públicas da cidade do Recife, Nordeste do Brasil, no período de agosto de 2007 a junho de 2009. Foram alocados 276 pares de mãe-filho, em dois grupos de suplementação: 400.000 UI ou 200.000 UI de vitamina A. As concentrações de retinol das crianças e materna foram analisadas pela cromatografia líquida de alta resolução-HPLC. Os resultados mostraram uma prevalência de 4,6% (IC95% 2,2 - 9,2) de baixas concentrações de retinol (< 0,70 μmol/L) e 72,9% (IC95% 66,6-79,7) de anemia (< 11g/dL) nas crianças aos seis meses e que houve associação entre o retinol sérico e hemoglobina (p=0,002). As médias das concentrações séricas de retinol foram semelhantes entre os dois grupos de suplementação (p = 0.514), e a média do retinol aos 2 meses foi significativamente menor que a média de retinol aos quatro meses (p < 0.001), mantendo um nível crescente até o sexto mês. Conclui-se que não foram detectados efeitos adicionais nas concentrações séricas de retinol das crianças após suplementação materna com dupla megadose de vitamina A no pós-parto e que as concentrações de retinol sérico mostraram uma tendência crescente até o sexto mês. Os dados também apontaram para uma baixa prevalência de hipovitaminose A na população aos seis meses e houve uma alta prevalência de anemia nas crianças o que reforça ainda tratar-se de um problema de grande magnitude na população infantil. / The aims of the present study were 1) to compare the impact of maternal supplementation with 400,000 UI vs 200,000 UI of vitamin A in the immediate postpartum period on serum concentrations of retinol in newborns, 2) estimate the duration of the protective effect on the maintenance of serum concentrations of retinol, 3) determine the prevalence of vitamin A deficiency and anemia at six months of age and 4) determine the association between concentrations of retinol and hemoglobin in infants. A hospital-based, randomized, controlled, triple-blind, clinical trial was carried out a two public maternities in the city of Recife (northeastern Brazil) between August 2007 and June 2009. A total of 276 mother/child pairs were divided into two groups: supplementation with 400,000 UI or 200,000 UI of vitamin A. Retinol concentrations in the infants and mothers were analyzed through high-resolution liquid chromatography. The results reveal a 4.6% (95%CI: 2.2 to 9.2) prevalence of low concentrations of retinol (< 0.70 μmol/L) and a 72.9% (95%CI: 66.6 to 79.7) prevalence of anemia (< 11 g/dL) in the infants at six months of age. A significant association was found between serum retinol and hemoglobin (p = 0.002). Serum concentrations of retinol were similar between the two supplementation groups (p = 0.514). Mean retinol at two months of age was significantly lower than at four months of age (p < 0.001) and maintained an increasing level through to six months of age. In conclusion, no additional effects on the serum concentrations of retinol in infants were detected following maternal supplementation with a double megadose of vitamin A in the postpartum period and serum retinol concentrations demonstrated an increasing tendency through to six months of age. The data also point to a low prevalence of vitamin A deficiency and high prevalence of anemia in the infants at six months of age, demonstrating that anemia remains a huge problem in the child population.

The purpose of this research was to study vitamin A status in grazing horses throughout the year and to evaluate the effectiveness of vitamin A and β-carotene as supplements. Vitamin A status was assessed by serum retinol concentrations (SR) and the relative dose response (RDR) which was adapted for use in the horse. The horses (45 Thoroughbred mares) were divided into three diet groups: pasture and hay only (PH); pasture, hay and vitamin A-free concentrate (PHC); and hay and vitamin A-free concentrate (HC). The mares, as well as their foals, were assessed for vitamin A status during the summer, fall and winter. After eight months, each diet group was subdivided and supplemented with either: retinyl palmitate at two times the recommended level (A), the equivalent in water dispersible β-carotene (B), or a placebo (C). Supplementation continued for 20 months during which the vitamin A status was assessed every 60 days in the mares, and at birth in the neonates. During both the depletion and the repletion phase the mares were kept on a regular breeding schedule and the reproductive rates were determined as well as the general health of the mares and their offspring. The RDR proved more sensitive at detecting changes in vitamin A status than SR, and a combination of both was used. A measurable decline in vitamin A stores was seen in the HC group within 2 months, and in PH and PHC groups during the winter. The HC group remained lower in vitamin A status throughout the study. A seasonal fluctuation of vitamin A status was observed regardless of supplementation. Supplementation with retinyl palmitate improved vitamin A status in all three diet groups, however, supplementation with β-carotene did not. Both neonates and young growing horses were lower in vitamin A status than the adult. A respiratory infection observed in the weanlings affected vitamin A status as well. Supplementation of the dam had no effect on neonatal vitamin A status. Deleterious effects on reproductive rates and health were also observed with vitamin A depletion. Supplementation of β-carotene had a negative effect on reproductive rates in this study. / Ph. D.

Made available in DSpace on 2015-04-17T15:03:06Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1807154 bytes, checksum: 7aebebd024c49081a819ffba28e2ccae (MD5) Previous issue date: 2010-05-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The aging population is one of the main results of demographic trends during the twentieth century. Anatomical and functional changes typical of aging can lead to specific deficiencies of nutrients. Vitamin A plays a key role in numerous physiological functions and the serum retinol concentrations are related to organic resistance against infections. Researches aimed at the diagnosis of vitamin A deficiency should include the analysis of serum concentrations of inflammatory markers in acute phase such as C-reactive protein in order to enable better expression of the vitamin A status. This study aimed to evaluate the importance of the habitual dietary vitamin A intake on the serum retinol concentrations in elderly people. This is a cross-section population-based epidemiological study conducted in João Pessoa / PB / Brazil in the period from 2008 to 2009 with 212 individuals between 60 and 90 years of age, from both genders. Data were collected for habitual food intake, retinolemia, C - reactive protein (CRP), and socioeconomic and anthropometric aspects. The mean vitamin A intake was 1643.40 &#956;g RAE / day (p25 = 1112.20 - p75 = 2430.80). The average serum retinol concentration was 1.91 ± 0.68 &#956;mol/L. There was no correlation between CRP concentration and serum retinol (r = 0.061 / p = 0.424), nor with habitual dietary retinol consumption (r = 0.000 / p = 0.932). However, there was a direct relationship between consumption and serum retinol levels (r = 0.173 / p = 0.025). Only 3,98% (IC95% 6,88 1,08) of subjects had inadequate serum retinol concentrations (<1.05 mmol / L), and 12.4% (CI 95% 17.36 to 7.44) Inadequate vitamin A intake (<625&#956;g, males and <500&#956;g, females). The elderly population from the municipality of João Pessoa / Paraíba / Brazil revealed a proper retinolemia status and habitual vitamin A intake and no correlation was found between CRP concentration and dietary serum retinol, probably because the sample was composed of elderly patients with no acute infection or absence of decompensated chronic diseases. The present study emphasizes the influence of dietary preformed vitamin A intake on the serum retinol concentrations, which seems to be an affective strategy to combat vitamin A deficiency in this population. / O envelhecimento da população foi um dos principais resultados das tendências demográficas populacionais durante o século XX. As mudanças anatômicas e funcionais próprias do envelhecimento podem levar a deficiências específicas de nutrientes. A vitamina A exerce ação essencial em inúmeras funções fisiológicas e as concentrações séricas dos retinoides estão relacionadas à resistência orgânica contra infecções. Pesquisas direcionadas ao diagnóstico da deficiência de vitamina A devem incluir a análise da concentração sérica de marcadores inflamatórios de fase aguda, como a proteína C-reativa, com a finalidade de possibilitar uma melhor expressão do estado vitamínico A. O presente trabalho teve como objetivo avaliar a importância do consumo alimentar habitual de vitamina A nas concentrações séricas de retinol em idosos. Estudo epidemiológico transversal, de base populacional, realizado em João Pessoa/PB/Brasil no período de 2008-2009, com 212 indivíduos de 60 e 90 anos de idade, de ambos os gêneros. Coletou-se dados de consumo alimentar habitual, retinolemia e Proteína C-Reativa (PCR), além de aspectos socioeconômicos e antropométricos. A mediana de consumo de vitamina A foi de 1643,40 &#956;g RAE/dia (p25 = 1112,20 - p75 = 2430,80). A concentração média de retinol sérico foi de 1,91 ± 0,68 &#956;mol/L. Não houve correlação entre concentração de PCR com o retinol sérico (r = 0,061/ p = 0,424), nem com o consumo alimentar habitual de retinol (r =0,000/ p = 0,932). No entanto, houve relação direta entre o consumo e os valores séricos de retinol (r =0,173 /p = 0,025). Apenas 3,98% (IC95% 6,88 1,08) dos indivíduos apresentaram concentrações de retinol sérico inadequados (< 1,05 &#956;mol/L), e 12,4% (IC95% 17,36 7,44) consumo de vitamina A inadequado (< 625&#956;g, gênero masculino e < 500&#956;g, feminino). Na população de idosos do município de João Pessoa/Paraíba/Brasil evidenciou-se adequado estado de retinolemia, e de consumo alimentar habitual de vitamina A e não encontrou-se correlação entre concentração de PCR com retinol sérico e dietético, provavelmente por tratar-se de idosos sem quadro agudo de infecção ou com ausência de doenças crônicas descompensadas. Destaca-se no presente estudo, a influência do consumo alimentar de vitamina A pré-formada nas concentrações séricas de retinol, o que parece ser uma estratégia efetiva no combate a hipovitaminose A nesta população.